<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="../react18/react.development.js"></script>
  <script src="../react18/react-dom.development.js"></script>
  <script src="../react18/babel.min.js"></script>
</head>
<body>
    <div id="app"></div>
    <script  type="text/babel">
        class App extends React.Component{
            state={
                mun: 0
            }
            render(){
                const {mun}= this.state;
                return(
                    <div>
                        <button onClick={this.handle}>+</button>
                        <p>{mun}</p>
                    </div>
                )
            }
              handle=()=>{
                const {mun}= this.state;
               this.setState({mun:mun+9

               })
            }
        }
        const root = ReactDOM.createRoot(document.getElementById('app'));
        root.render(<App/>)
    </script>
</body>
</html>